1. Field
The following description relates to a source driver, and more particularly, to a slew rate boost circuit for an output buffer and an output buffer for a source driver having the same.
2. Description of the Related Art
In a liquid crystal display (LCD) apparatus which is a representative flat panel display, a maximum driving frequency increases as resolution increases. Therefore, a source driver for driving the liquid crystal panel of the liquid crystal display apparatus should drive a desired target value in a short time. However, as a load of the liquid crystal panel increases, the slew rate of the source driver decreases. The slew rate shows how fast an output signal catches up with an input signal, and represents a gradient of time versus voltage. If the slew rate is small, the source driver may not provide a desired target value to the liquid crystal panel, thereby degrading image quality.
Increasing the size of a drive transistor of an output buffer could be a way to obtain a high slew rate in a source drive with heavy load. However, this method requires a large space, and thus, drives up a cost.